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Mammal Review


A questionnaire, data from a public participation survey, past records and nestbox counts were used to review Dormouse distribution and status in Wales. At the turn of the century Dormice were reported from all Welsh counties. In the three decades from 1940 they were known from only seven l-km squares; this rose to 26 squares in the 1970s after a Mammal Society survey. Dormice are currently (1990-93) known from 107 1-km squares, only 0.5% of Wales, and are clearly rare. They have recently been 'rediscovered' in North Wales and Glamorgan. However, despite an increase in recording effort, very few sites have been found in northern Wales, implying a decline in status, and relatively few in the west compared to the east. Large tracts of Dyfed and Powys, where there is some suitable habitat, seem to lack Dormice. More than half of known Dormouse sites are in the deciduous margins of conifer plantations (36%) or in oak Quercus spp. woods (22%), both likely to be poor-quality habitats. Population densities at three sites are within the range of those measured in England. Forty per cent of known sites had some protected status, but 53% of sites were considered threatened, due to clear felling during forestry operations or lack of coppice woodland management. Dormouse distribution in Wales, on the western edge of the species' distributional range, seems to be strongly restricted by habitat suitability and climate. Many populations are likely to be threatened by replanting of ancient woodland and subsequent management harmful to the Dormouse's needs. Only 11% of ancient woodlands in Wales are large (> 20 ha). Dormice may therefore often occur in small woods, where their survival is likely to depend critically on the maintenance of hedgerows between woods. A programme of practical conservation and research is proposed to safeguard Dormouse populations.

Author(s): BRIGHT, PW

Journal: Mammal Review

Year: 1995